Ohana has shoes, decks, hoodies, and t-shirts. I think they may have the Spitfire JR wheels too.
Surf Specialties has hoodies, and at least one full JR board with his last deck design, thunder trucks, and JR wheels.
In Houston Surfhouse has JR decks and wheels, and they may also have the t-shirts and hoodies. There may be a few other shops that have Johnny's stuff, so you should check with your local shop first.